Retinal tears can occur when the vitreous, a clear gel-like substance that fills the centers of the eye, pulls away from the retina thereby leaving behind a tear or hole in the retina. Rhegmatogenous retinal detachments can result if the retinal breaks, i.e. tears or holes in the retina of an eye are not treated. With retinal breaks, fluid from the vitreous apparently seeps through the retinal break and accumulates under the retina. The degree of detachment is measured by the volume of subretinal fluid as well as the area of the retina involved. Some symptoms of retinal detachment include the presence of floaters, flashes, shadows or blind area, decreased visual acuity and metamorphopsia.
A number of techniques are employed for treating retinal detachments including using a scleral buckle, pneumatic retinopexy, cryopexy (i.e., freezing) and photocoagulation using a laser or xenon arc light source. These techniques may be used alone or in combination with each other to treat the retinal detachments for example, a combination of using a scleral buckle and photocoagulation. Additional retinal tears with little or no nearby detachment can be treated using photocoagulation or cryopexy.
In the photocoagulation technique when using a laser, the retinal break is surrounded with one or more rows of a plurality of laser burns or laser heat spots. These laser heat spots or burns produce scars, which prevents fluid from passing through and collecting under the retina. In the photocoagulation procedure, a gas is exchanged for the vitreous fluid being aspirated from within the eye so the gas is intraocular when performing photocoagulation. Typically, the gas is air from a tank that may be filtered and sterilized before it is infused into the eye.
Such air infusion of into the eye, however, can be quite problematic. For example, the infused air often can cause the lens of a patient's eye to become cloudy and dry, complicating the surgical procedure and creating conditions that can result in injury to the patient.
It thus would be desirable to have improved devices, systems and methods for infusing a gas, particularly air, to a patient's eye during eye surgery procedures. It would be particularly desirable to have improved devices, systems and methods for infusing air or other gas to a patient's eye during surgery wherein the eye lens remains substantially clear and moist.